EL11

Power/output pentode designed for audio-frequency power amplification in single-ended or push-pull output stages.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: Y8A
Base pins: 8
Nominal heater: 6.3 V / 900 mA

Description

Audio power output pentode for class-A and push-pull amplifier service.

Socket description

Steel-tube 8-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: Y8A
Base pins: 8
Nominal heater voltage: 6.3 V
Nominal heater current: 900 mA
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances

Plate resistance: 30000 Ω
Transconductance: 0.009 S
Max plate voltage: 425 V
Max screen voltage: 425 V
Max plate dissipation: 18 W
Max screen dissipation: 2.8 W
Max cathode current: 100 mA

Published ratings and characteristics promoted where clearly stated; identical repeated sections compressed where applicable.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1953 RFT Rundfunk Technik

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

HeaterVoltageNominal
6.3 V
Nominal
HeaterCurrentNominal
900 mA
Nominal
Maximum Plate Voltage
425 V
Maximum Screen Voltage
425 V
Maximum Plate Dissipation
18 W
Maximum Screen Dissipation
2.8 W
Maximum Cathode Current
100 mA

Characteristic

Transconductance
11000 µS
Typical
Plate Resistance
30000 ohm
Typical

Data set 02

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

Plate voltage
250 V
ClassA
Screen-grid voltage
250 V
ClassA
Control-grid voltage
-6 V
ClassA
Plate current
36 mA
ClassA
Screen-grid current
4 mA
ClassA
Cathode resistor
150 Ohm
ClassA
Load resistance
7000 Ohm
ClassA
Output power
4.5 W
ClassA
Plate cold voltage
550 V
Screen-grid cold voltage
550 V
Triode-connection output power
1.2 W
TriodeConnection;ClassA

Capacitance

Grid-to-plate capacitance
0.8 pF

Characteristics

Triode-connection transconductance
8000 uS
TriodeConnection;Va=250V
Triode-connection plate resistance
3500 Ohm
TriodeConnection;Va=250V

Data set 03

1999 Philips E-Z

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

Capacities Cagl
< 0.8 pF
Wo 0
8.2 W

Other

Va
250 V
ClassA
Va2
250 V
ClassA
Vg1
-6 V
ClassA
Ig2 = 4 mh
9 mA/V
ClassA
Va
250 v
ClassA
Vg2
250 v
ClassA
Ia = 2x24
2x28.5 mA
ClassA
ig2 = 2x2,8
2x44.6 mA
ClassA
Va, =max [1]
550 V
Va, =max [2]
0 V
Va, =max [3]
1.2 W
va =max [1]
250 V
va =max [2]
2.5 W
VWa =max [1]
9 W
VWa =max [2]
0.3 pA
VWa =max [3]
-1.3 V
Vg2 =max
275 V
Ik =pmax [1]
55 mA
Ik =pmax [2]
50 V